[PATCH] platform/x86: lenovo-wmi-other: fix uninitialized variable in lenovo wmi-other driver

[Yufei CHENG <cd345al@gmail.com>]

When the flag relax_fan_constraint is set, local variable 'raw'
is never assigned, and lwmi_om_hwmon_write() will pass uninitialized
value to lwmi_om_fan_get_set() resulting in undefined behavior.

This flag allows user to bypass minimum fan RPM divisor rounding,
but assignment to 'raw' only happens in the non-relaxed path.
Fix by defaulting 'raw' to user provided 'val' in the else branch.

Fixes: 51ed34282f63fab5b3996477cc56135eb4de5284
Signed-off-by: Yufei CHENG <cd345al@gmail.com>
---
 drivers/platform/x86/lenovo/wmi-other.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/platform/x86/lenovo/wmi-other.c b/drivers/platform/x86/lenovo/wmi-other.c
index 6040f45aa..6c2febe1a 100644
--- a/drivers/platform/x86/lenovo/wmi-other.c
+++ b/drivers/platform/x86/lenovo/wmi-other.c
@@ -349,6 +349,8 @@ static int lwmi_om_hwmon_write(struct device *dev, enum hwmon_sensor_types type,
 			 */
 			if (!relax_fan_constraint)
 				raw = val / LWMI_FAN_DIV * LWMI_FAN_DIV;
+			else
+				raw = val;
 
 			err = lwmi_om_fan_get_set(priv, channel, &raw, true);
 			if (err)
-- 
2.43.0